1. Field of the Invention
The present invention relates to a collision determination device that determines a possibility of contact of an own vehicle with a three-dimensional object ahead of the own vehicle detected by a stereo camera, a single-lens camera or a millimeter wave radar, and to a vehicle behavior control device that operates an appropriate actuator to guide the own vehicle to travel on the most favorable path, thereby controlling the vehicle behavior based on the possibility of contact.
2. Related Art
Recently, more vehicles have mounted multiple vehicle behavior control devices such as automatic braking devices and four-wheel drive control devices. Techniques have been proposed to integrate these vehicle behavior control devices (for example, JP-A-2003-191774).
Further, a driving assistance control device have been proposed that use a car-mounted camera to photograph a front traveling environment and recognize a three-dimensional object in a front to estimate a possibility of collision of the own vehicle with such a three-dimensional object (for example, JP-A-2004-037239).
While precise recognition of the position of a three-dimensional object ahead is required of such a device for estimating the possibility of collision between the three-dimensional object ahead and the own vehicle, detection using a camera includes an error. It is thus necessary to identify the position of a three-dimensional object ahead while considering the error.
JP-A-2004-037239 discloses a technique where, based on the normal distribution concerning the positional/velocity errors occurring when each of the plurality of sensors has detected a same object, first and second probabilities are calculated as probabilities of each of the detected objects being the same object in terms of position and velocity from the identified positional and velocity errors and a third probability is calculated as a probability of each of the detected objects being the same object based on the first probability and the second probability, and in case the third probability has exceeded a threshold, each of the detected objects is determined as the same object.
However, as disclosed in JP-A-2004-037239, it is impossible to correctly estimate a change of position of the three-dimensional object ahead before it comes into contact with the own vehicle even in case the current position of the three-dimensional object is correctly determined. Such uncertainties become more serious as an error caused by a camera for detecting the three-dimensional object ahead becomes large. A more practical system is desirable that considers such uncertainties in the control of a vehicle.
Further, the vehicle behavior control device disclosed in JP-A-2003-191774 does not consider integration with a driving assistance control device such as one disclosed in JP-A-2004-037239. Thus, coordinated control with the driving assistance control device is not very efficient. In terms of coordination between the vehicle behavior control device disclosed in JP-2003-191774 and the driving assistance control device disclosed in JP-A-2004-037239, a problem must be solved of how to effectively share the control amount by the vehicle behavior control device and the control amount by the driving assistance control device.
The invention has been accomplished in view of the aforementioned circumstances. An object of the invention is to provide a collision determination device that estimates the possibility of a three-dimensional object a head being contact with an own vehicle by a statistical processing without correctly obtaining the position of the three-dimensional object so as to control the own vehicle with a natural feel.
In addition, another object of the invention is to provide a vehicle behavior control device capable of efficiently and stably performing the above coordinated control.